From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-19.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9A892C636C9 for ; Thu, 15 Jul 2021 18:43:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 834E0613F5 for ; Thu, 15 Jul 2021 18:43:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237439AbhGOSqF (ORCPT ); Thu, 15 Jul 2021 14:46:05 -0400 Received: from mail.kernel.org ([198.145.29.99]:47000 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237518AbhGOSqA (ORCPT ); Thu, 15 Jul 2021 14:46:00 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 9D258613CA; Thu, 15 Jul 2021 18:43:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1626374587; bh=5+gQWr/yUf/ad/b9w3djbtGAt44Gg7Xp0cfmZQse++Y=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=rX6dRGDHuLHcFTyKZSppSSHIuSDVOpLu+ZRTISRLdhu0KhtBksCgCMTInhq07snpC ty/efvBsMNJBHtfAlZnumW+3QHQ2DckQRaSZtxcYv2AYSsNPIggIvCafBvjXHtJIjk E+caDh2dYb/9qxVrCO9jTUBlXYAGBbqFQ3a8FPN8= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Sean Young , Daniel Borkmann , Sasha Levin Subject: [PATCH 5.4 061/122] media, bpf: Do not copy more entries than user space requested Date: Thu, 15 Jul 2021 20:38:28 +0200 Message-Id: <20210715182505.782707516@linuxfoundation.org> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20210715182448.393443551@linuxfoundation.org> References: <20210715182448.393443551@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Sean Young [ Upstream commit 647d446d66e493d23ca1047fa8492b0269674530 ] The syscall bpf(BPF_PROG_QUERY, &attr) should use the prog_cnt field to see how many entries user space provided and return ENOSPC if there are more programs than that. Before this patch, this is not checked and ENOSPC is never returned. Note that one lirc device is limited to 64 bpf programs, and user space I'm aware of -- ir-keytable -- always gives enough space for 64 entries already. However, we should not copy program ids than are requested. Signed-off-by: Sean Young Signed-off-by: Daniel Borkmann Link: https://lore.kernel.org/bpf/20210623213754.632-1-sean@mess.org Signed-off-by: Sasha Levin --- drivers/media/rc/bpf-lirc.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/media/rc/bpf-lirc.c b/drivers/media/rc/bpf-lirc.c index 0a0ce620e4a2..d5f839fdcde7 100644 --- a/drivers/media/rc/bpf-lirc.c +++ b/drivers/media/rc/bpf-lirc.c @@ -329,7 +329,8 @@ int lirc_prog_query(const union bpf_attr *attr, union bpf_attr __user *uattr) } if (attr->query.prog_cnt != 0 && prog_ids && cnt) - ret = bpf_prog_array_copy_to_user(progs, prog_ids, cnt); + ret = bpf_prog_array_copy_to_user(progs, prog_ids, + attr->query.prog_cnt); unlock: mutex_unlock(&ir_raw_handler_lock); -- 2.30.2